First, the valve Solenoid valve Solenoid valve Solenoid valve Check valve Cartridge valve Cartridge valve Cartridge valve Sandwich plate valve Pilot valve Pilot operated check valve Pilot operated check valve Pilot operated check valve Sub-plate mount Manifold block Manifold block Pressure relief valve Pressure Relief Valve Flow valve Throttle valve Throttle valve Throttle valve Throttle valve Double throttle check valve Rotary knob Knobs Rectifier plate Throttle valve Servo valve Servo valve Proportional valve Proportional valve Position feedback Position feedback Progressive flow De-energizing of solenoid Electromagnet release Second, the media Phosphate ester (HFD-R) Phosphate ester water-glycol (HFC) Water - Ethylene glycol Emulsion Emulsion Inhibitor Inhibitor Synthetic lubricating oil Third, the hydraulic installation works Contamination Pollution Grout Grouting Failure Failure Jog Jog Creep Creep Abrasion Friction Retract Extension Out of Piston Retract Malfunction Malfunction Pickling Pickling Flushing Flushing Dipping process Pickling Re-circulation Passivity Passivation Nitric acid Citric Acid Argon Argon Butt Butt Butt Welding Butt Welding Butt Welding Butt Welding Butt Welding Inert gas welding Inert Gas Welding IV.Fittings Bite type Fittings Tube Fittings Tube to tube fittings Union Fittings Union Fittings union elbow Fittings union tee Three-way union union cross Four-way joint Mal stud fittings End straight union fittings Bulkhead fittings Long straight union fittings Weld fittings Welded fittings Female connector fittings Union nuts Reducers extenders Reducing union fittings Banjo fittings Articulated fittings Adjustable fittings / swivel nut Rotary Joints V. Servo and Servo System Performance Parameters Dynamic response DDV-direct drive valve NFPA-National Fluid Power Association Phase lag Phase lag Nozzle flapper valve Servo- jet pilot valve Jet valve Dither Flutter current Coil impedance Coil impedance Flow saturated Saturation Linearity Linearity Symmetry Symmetry Hysterics Hysteresis Threshold Sensitivity Lap Lap Pressure Pressure increase Null zero Null bias Null bias Null bias Frequency response Slope curve Ramp